Fig. 2. Effect of twice-daily intraperitoneal injection of vehicle, 50 mg · kg−1· day−1or 100 mg · kg−1· day−1minocycline for 3 days ( A ) and 7 days ( B ) in the postoperative pain model. Withdrawal thresholds were not altered after treatment. The hind paw withdrawal thresholds (g) are shown as mean ± SEM (n = 8 for each group).